Torge Husfeldt has posted code for this. you can find it here:
http://swiki.gsug.org:8080/sqfixes/2657.html

I had difficulties with filing this in (Syntax error, "Argument expected" after the second doIt, both on 2.3-4596 and 3.4a-5109), but could do it after moving the doIts from the preamble to the postscript (they only add preferences, I think this should be safe)

so if you have trouble with the original, too, try the attached version.

HTH,
Joern

Markus Fritsche wrote:
> 
> Hi!
> 
> Is there a preference value that controls how marking text (shift+arrow)
> works? I would like to have the "kde" behaviour that remembers where the
> marking started and marks text relativly to that position (meaning:
> Shift+ ( -> -> <- <- <-) results in on char marked to the left of
> position where the action started and not in three signs to the left and
> two to the right, als in 'native' squeak).
> 
> Regards, Markus
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